Patients with renal cell carcinoma nodal metastases can be accurately identified: external validation of a new nomogram

Multimodal data integration using machine learning to predict the risk of clear cell renal cancer metastasis: a retrospective multicentre study

PURPOSE

To develop and validate a predictive combined model for metastasis in patients with clear cell renal cell carcinoma (ccRCC) by integrating multimodal data.

MATERIALS AND METHODS

In this retrospective study, the clinical and imaging data (CT and ultrasound) of patients with ccRCC confirmed by pathology from three tertiary hospitals in different regions were collected from January 2013 to January 2023. We developed three models, including a clinical model, a radiomics model, and a combined model. The performance of the model was determined based on its discriminative power and clinical utility. The evaluation indicators included area under the receiver operating characteristic curve (AUC) value, accuracy, sensitivity, specificity, negative predictive value, positive predictive value and decision curve analysis (DCA) curve.

RESULTS

A total of 251 patients were evaluated. Patients (n = 166) from Shandong University Qilu Hospital (Jinan) were divided into the training cohort, of which 50 patients developed metastases; patients (n = 37) from Shandong University Qilu Hospital (Qingdao) were used as internal testing, of which 15 patients developed metastases; patients (n = 48) from Changzhou Second People's Hospital were used as external testing, of which 13 patients developed metastases. In the training set, the combined model showed the highest performance (AUC, 0.924) in predicting lymph node metastasis (LNM), while the clinical and radiomics models both had AUCs of 0.845 and 0.870, respectively. In the internal testing, the combined model had the highest performance (AUC, 0.877) for predicting LNM, while the AUCs of the clinical and radiomics models were 0.726 and 0.836, respectively. In the external testing, the combined model had the highest performance (AUC, 0.849) for predicting LNM, while the AUCs of the clinical and radiomics models were 0.708 and 0.804, respectively. The DCA curve showed that the combined model had a significant prediction probability in predicting the risk of LNM in ccRCC patients compared with the clinical model or the radiomics model.

CONCLUSION

The combined model was superior to the clinical and radiomics models in predicting LNM in ccRCC patients.

Development and validation of prognostic nomograms for adult with papillary renal cell carcinoma: A retrospective study

OBJECTIVE

The aim of the study was to create two consensus nomograms for predicting Overall Survival (OS) and Cancer-Specific Survival (CSS) in adults with papillary Renal Cell Carcinoma (pRCC).

METHODS

Using the Surveillance, Epidemiology, and End Results databases, a retrospective analysis of 1,074 adults with pRCC from 2004 to 2015 was performed. These patients were then randomly divided into two independent cohorts with a ratio of 7:3 (training cohort: 752; validation cohort: 322). In a retrospective analysis of 752 patients from the training cohort, independent prognostic variables affecting OS and CSS were found. R software was used to create prognostic nomograms based on the findings of Cox regression analysis. The performance of the nomograms was assessed using the Concordance Index (C-index), the Area Under Curve (AUC), a calibration curve, and Decision Curve Analysis (DCA). Data from the 107 postoperative pRCC patients at the Affiliated Hospital of Xuzhou Medical University were used for external validation of the nomogram.

RESULTS

For OS and CSS, the C-indices and AUCs of the training cohort and the validation cohort indicated that the model had excellent discrimination. The DCA demonstrated that the model was clinically applicable, and the calibration curves in the internal and external validations showed that the model's accuracy was high.

CONCLUSION

The authors developed and validated a prognostic nomogram that accurately predicted the 3-, 5-, and 8-year OS and CSS of adults with pRCC. Clinicians can use this knowledge to direct the clinical management and counseling of patients with pRCC.

Should Patients with Renal Cell Carcinoma and Pathological Nodal Invasion Be Classified As Having Stage IV Disease?

BACKGROUND

Lymph node invasion is associated with poor outcome in patients with renal cell carcinoma (RCC).

PATIENTS AND METHODS

Patients with RCC within a single center from 2001 to 2018 were retrospectively obtained from the Chang Gung Research Database. Patient gender, physical status, Charlson Comorbidity Index, tumor side, histology, age at diagnosis, and body mass index (BMI) were compared. The overall survival (OS) and cancer-specific survival (CSS) of each group were estimated using the Kaplan-Meier method. Log-rank tests were used to compare between the subgroups.

RESULTS AND CONCLUSIONS

A total of 335 patients were enrolled, of whom 76 had pT3N0M0, 29 had pT1-3N1M0, 104 had T1-4N0M1, and 126 had T1-4N1M1 disease. Significant OS difference was noted between pT3N0M0 and pT1-3N1M0 groups with 12.08 years [95% confidence interval (CI), 8.33-15.84] versus 2.58 years (95% CI, 1.32-3.85), respectively (P < 0.005). No significant difference was observed in OS between pT1-3N1M0 and T1-4N0M1 groups with 2.58 years (95% CI, 1.32-3.85) versus 2.50 years (95% CI, 1.85-3.15, P = 0.72). The OS of N1M1 group was worse than that of N0M1 group with 1.00 year (95% CI, 0.74-1.26) versus 2.50 years (95% CI, 1.85-3.15, P < 0.05). Similar results were also observed in CSS. In summary, we claim that RCC with lymph node (LN) invasion should be reclassified as stage IV disease in terms of survival outcome.

The Current Role of Lymph Node Dissection in Nonmetastatic Localized Renal Cell Carcinoma

PURPOSE

To explore the current role of lymph node dissection (LND) in the management of nonmetastatic localized renal cell carcinoma (RCC).

BACKGROUND

There is currently no proven benefit of LND in the setting of RCC, and its role remains controversial because of conflicting evidence. Patients who may benefit from LND are those at greatest risk of nodal disease, but the tools used to predict nodal involvement are limited due to unpredictable retroperitoneal lymphatics. The indications, templates, and extent of LND are also not standardized, adding to the ambiguity of current guidelines surrounding its use.

EVIDENCE ACQUISITION

A PubMed search of the literature from January 2017 to December 2022 was conducted using the search terms "renal cell carcinoma" or "renal cancer" in combination with "lymph node dissection" or "lymphadenectomy". Case studies and editorials were excluded, whereas studies investigating the therapeutic effect of LND were classified as either demonstrating a benefit or no benefit. References of the studies and review articles were also searched for notable studies and findings that were outside the five-year literature search. The studies in this review were restricted to the English language.

RESULTS

Only a number of studies in recent years have found an association between the extent of LND and increased survival. Most studies do not indicate an associated benefit, and some even suggest a negative effect on survival. Most of these studies are retrospective.

CONCLUSION

The therapeutic value of LND in RCC is still unclear, and although prospective data are needed, its declining rates and emerging new therapies make this unlikely. A better understanding of renal lymphatics and improved detection of nodal disease may help determine the role of LND in nonmetastatic localized RCC.

Potential benefit of lymph node dissection during radical nephrectomy for kidney cancer: A review and critical analysis of current literature

Objective

The role of lymph node dissection (LND) is still controversial in patients with renal cell carcinoma undergoing surgery. We aimed to provide a comprehensive review of the literature about the effect of LND on survival, prognosis, surgical outcomes, as well as patient selection and available LND templates.

Methods

Recent literature (from January 2011 to December 2021) was assessed through PubMed and MEDLINE databases. A narrative review of most relevant articles was provided.

Results

The frequencies in which LNDs are being carried out are decreasing due to an increase in minimally invasive and nephron sparing surgery. Moreover, randomized clinical trials and meta-analyses failed to show any survival advantage of LND versus no LND. However, retrospective studies suggest a survival benefit of LND in high-risk patients (bulky tumors, T3-4 stage, and cN1 patients). Moreover, extended LND might provide important staging information, which could be of interest for adjuvant treatment planning.

Conclusion

No level 1 evidence of any survival advantage deriving from LND is currently available in literature. Thus, the role of LND is limited to staging purposes. However, low grade evidence suggests a possible role of LND in high-risk patients. Randomized clinical trials are warranted to corroborate these findings.

Development and Validation of a Nomogram to Predict Distant Metastasis in Elderly Patients With Renal Cell Carcinoma

Background

Renal cell carcinoma (RCC) is the most common renal malignant tumor in elderly patients. The prognosis of renal cell carcinoma with distant metastasis is poor. We aim to construct a nomogram to predict the risk of distant metastasis in elderly patients with RCC to help doctors and patients with early intervention and improve the survival rate.

Methods

The clinicopathological information of patients was downloaded from SEER to identify all elderly patients with RCC over 65 years old from 2010 to 2018. Univariate and multivariate logistic regression analyzed the training cohort's independent risk factors for distant metastasis. A nomogram was established to predict the distant metastasis of elderly patients with RCC based on these risk factors. We used the consistency index (C-index), calibration curve, and area under the receiver operating curve (AUC) to evaluate the accuracy and discrimination of the prediction model. Decision curve analysis (DCA) was used to assess the clinical application value of the model.

Results

A total of 36,365 elderly patients with RCC were included in the study. They were randomly divided into the training cohort (N = 25,321) and the validation cohort (N = 11,044). In the training cohort, univariate and multivariate logistic regression analysis suggested that race, tumor histological type, histological grade, T stage, N stage, tumor size, surgery, radiotherapy, and chemotherapy were independent risk factors for distant metastasis elderly patients with RCC. A nomogram was constructed to predict the risk of distant metastasis in elderly patients with RCC. The training and validation cohort's C-indexes are 0.949 and 0.954, respectively, indicating that the nomogram has excellent accuracy. AUC of the training and validation cohorts indicated excellent predictive ability. DCA suggested that the nomogram had a better clinical application value than the traditional TN staging.

Conclusion

This study constructed a new nomogram to predict the risk of distant metastasis in elderly patients with RCC. The nomogram has excellent accuracy and reliability, which can help doctors and patients actively monitor and follow up patients to prevent distant metastasis of tumors.

Development and validation of a machine learning model to predict the risk of lymph node metastasis in renal carcinoma

SIMPLE SUMMARY

Studies have shown that about 30% of kidney cancer patients will have metastasis, and lymph node metastasis (LNM) may be related to a poor prognosis. Our retrospective study aims to provide a reliable machine learning-based model to predict the occurrence of LNM in kidney cancer. We screened the pathological grade, liver metastasis, M staging, primary site, T staging, and tumor size from the training group (n=39016) formed by the SEER database and the validation group (n=771) formed by the medical center. Independent predictors of LNM in cancer patients. Using six different algorithms to build a prediction model, it is found that the prediction performance of the XGB model in the training group and the validation group is significantly better than any other machine learning model. The results show that prediction tools based on machine learning can accurately predict the probability of LNM in patients with kidney cancer and have satisfactory clinical application prospects.

BACKGROUND

Lymph node metastasis (LNM) is associated with the prognosis of patients with kidney cancer. This study aimed to provide reliable machine learning-based (ML-based) models to predict the probability of LNM in kidney cancer.

METHODS

Data on patients diagnosed with kidney cancer were extracted from the Surveillance, Epidemiology and Outcomes (SEER) database from 2010 to 2017, and variables were filtered by least absolute shrinkage and selection operator (LASSO), univariate and multivariate logistic regression analyses. Statistically significant risk factors were used to build predictive models. We used 10-fold cross-validation in the validation of the model. The area under the receiver operating characteristic curve (AUC) was used to assess the performance of the model. Correlation heat maps were used to investigate the correlation of features using permutation analysis to assess the importance of predictors. Probability density functions (PDFs) and clinical utility curves (CUCs) were used to determine clinical utility thresholds.

RESULTS

The training cohort of this study included 39,016 patients, and the validation cohort included 771 patients. In the two cohorts, 2544 (6.5%) and 66 (8.1%) patients had LNM, respectively. Pathological grade, liver metastasis, M stage, primary site, T stage, and tumor size were independent predictive factors of LNM. In both model validation, the XGB model significantly outperformed any of the machine learning models with an AUC value of 0.916.A web calculator (https://share.streamlit.io/liuwencai4/renal_lnm/main/renal_lnm.py) were built based on the XGB model. Based on the PDF and CUC, we suggested 54.6% as a threshold probability for guiding the diagnosis of LNM, which could distinguish about 89% of LNM patients.

CONCLUSIONS

The predictive tool based on machine learning can precisely indicate the probability of LNM in kidney cancer patients and has a satisfying application prospect in clinical practice.

CT Radiomics for the Prediction of Synchronous Distant Metastasis in Clear Cell Renal Cell Carcinoma

PURPOSE

The aim of this study was to construct and verify a computed tomography (CT) radiomics model for preoperative prediction of synchronous distant metastasis (SDM) in clear cell renal cell carcinoma (ccRCC) patients.

METHODS

Overall, 172 patients with ccRCC were enrolled in the present research. Contrast-enhanced CT images were manually sketched, and 2994 quantitative radiomic features were extracted. The radiomic features were then normalized and subjected to hypothesis testing. Least absolute shrinkage and selection operator (LASSO) was applied to dimension reduction, feature selection, and model construction. The performance of the predictive model was validated through analysis of the receiver operating characteristic curve. Multivariate and subgroup analyses were performed to verify the radiomic score as an independent predictor of SDM.

RESULTS

The patients randomized into a training (n = 104) and a validation (n = 68) cohort in a 6:4 ratio. Through dimension reduction using LASSO regression, 9 radiomic features were used for the construction of the SDM prediction model. The model yielded moderate performance in both the training (area under the curve, 0.89; 95% confidence interval, 0.81-0.97) and the validation cohort (area under the curve, 0.83; 95% confidence interval, 0.69-0.95). Multivariate analysis showed that the CT radiomic signature was an independent risk factor for clinical parameters of ccRCC. Subgroup analysis revealed a significant connection between the SDM and radiomic signature, except for the lower pole of the kidney subgroup.

CONCLUSIONS

The CT-based radiomics model could be used as a noninvasive, personalized approach for SDM prediction in patients with ccRCC.

Choice of Surgical Options in Kidney Cancer and Surgical Complications

Surgical resection of renal cell carcinoma plays a large role in the overall management of the disease. The gold standard for surgical management historically has been open or laparoscopic radical nephrectomy, however, evidence of equivalent oncologic efficacy with improved clinical outcomes has driven the use of nephron-sparing surgeries, especially for smaller and localized renal tumors. A role for surgery remains in metastatic RCC as well, but controversy exists as to which patients may benefit most from surgical intervention in addition to other systemic targeted therapies. This article focuses specifically on renal cell carcinoma, transitional cell carcinoma is not described here.

The Role of Lymphadenectomy in Patients with Advanced Renal Cell Carcinoma

The role of lymph node dissection (LND) in the management of renal cell carcinoma (RCC) is controversial. LND serves an indisputable staging role by providing pathologic nodal stage. However, while earlier observational studies had suggested a survival benefit to LND, more recent observational evidence and a randomized trial do not support a survival benefit. The majority of patients with isolated lymph node involvement appear to harbor occult metastatic disease. Still, LND is not associated with increased perioperative morbidity when performed in experienced centers. LND may therefore play a predominantly staging role in patients at increased risk of lymph node metastases.

Development and external validation of a pathological nodal staging score for patients with clear cell renal cell carcinoma

OBJECTIVES

To develop and externally validate a model that quantifies the likelihood that a pathologically node-negative patient with clear cell renal cell carcinoma (cRCC) has, indeed, no lymph node metastasis (LNM).

PATIENTS AND METHODS

Data from 1389 patients treated with radical nephrectomy (RN) and lymph node dissection (LND) were analyzed. For external validation, we used data from 2270 patients in the Surveillance, Epidemiology and End Results (SEER) database. We estimated the sensitivity of pathologic nodal staging using a beta-binomial model and developed a pathological nodal staging score (pNSS), which represents the probability that a patient is correctly staged as node negative as a function of the number of examined lymph nodes (LNs).

RESULTS

The mean and median number of LNs removed were 7.0 and 5.0 (standard deviation, SD 6.6; interquartile range, IQR 7.0) in the development cohort and 5.6 and 2.0 (SD 8.6, IQR 5.0) in the validation cohort, respectively. The probability of missing a positive LN decreased with increasing number of LNs examined. In both the validation and the development cohort, the number of LNs needed for correctly staging a patient as node negative increased with higher pathological tumor stage and Fuhrman grade.

CONCLUSIONS

The number of examined LNs needed for adequate nodal staging in cRCC depends on pathological tumor stage and Fuhrman grade. We developed here and then externally validated a pNSS, which could help to refine patient counseling, decision-making regarding risk-stratified surveillance regimens and inclusion criteria for clinical trials of adjuvant therapy.

BioScore (B7-H1, survivin, and Ki-67) does not predict cancer-specific mortality in surgically treated patients with renal cell carcinoma: An external validation study

BACKGROUND

To externally validate' BioScore', a biomarker-based scoring system using immunohistochemical tumor expression levels of B7-H1, survivin, and Ki-67, in a single-center cohort of renal cell carcinoma (RCC) patients. Additionally, we investigated the potential benefit of BioScore as compared to the Mayo Clinic stage, size, grade, and necrosis (SSIGN) score.

MATERIALS AND METHODS

The validation cohort comprised 393 nonmetastatic RCC patients treated with radical nephrectomy or nephron-sparing surgery from 1999 to 2004. Kaplan-Meier estimators, the log-rank test, uni- and multivariable Cox regression models, and measures of discrimination were used to quantify the prognostic performance of BioScore regarding cancer-specific mortality (CSM).

RESULTS

During a median follow-up of 7.8 years, 69/132 (52%) deaths were adjudicated to progressive disease. BioScore was weakly associated with CSM in univariable analysis (hazard ratio per 1 point increase = 1.12, 95% confidence interval = 1.02-1.23, P = 0.023). However, this association did not prevail after adjusting for other adverse prognostic factors as represented by the SSIGN score. The discriminative performance of BioScore was very modest (Harrell's C-Index = 0.60) and did not improve the SSIGN score (P = 0.341), which already showed an excellent discrimination, as evidenced by Harrell's C-Index of 0.81. In a sensitivity analysis regarding clear cell RCC patients only, B7-H1 positivity did not emerge as a statistically significant predictor of CSM.

CONCLUSION

Although a higher BioScore was significantly associated with a higher CSM, the magnitude of this association was weak and not independent from other prognosticators. Moreover, BioScore did not improve the prognostic accuracy of the SSIGN score.

Trends and outcomes of lymphadenectomy for nonmetastatic renal cell carcinoma: A propensity score-weighted analysis of the National Cancer Database

PURPOSE

Lymph node (LN) involvement in renal cell carcinoma (RCC) is associated with a poor prognosis. While lymph node dissection (LND) may provide diagnostic information, its therapeutic benefit remains controversial. Thus, the aim of our study is to analyze survival outcomes after LND for nonmetastatic RCC and to characterize contemporary practice patterns.

MATERIALS AND METHODS

The National Cancer Database was queried for patients with nonmetastatic RCC who underwent either partial or radical nephrectomy from 2010 to 2014. A total of 11,867 underwent surgery and LND. Chi-square tests were used to examine differences in patient demographics. To minimize selection bias, propensity score matching (PSM) was used to select one control for each LND case (n = 19,500). Cox regression analyses were conducted to examine overall survival (OS) in patients who received LND compared to those who did not.

RESULTS

Of all patients undergoing LND for RCC (n = 11,867), 5%, 23%, 31%, 47% were performed for tumors of clinical T stage 1, 2, 3, and 4, respectively. Proportions of LND have not significantly changed from 2010 to 2014. No significant improvement in median OS for patients undergoing LND compared to no LND was shown (34.7 vs. 34.9 months, respectively; P = 0.98). Similarly, no significant improvement in median OS was found for clinically LN positive patients undergoing LND compared to no LND (P = 0.90). On Cox regression analysis, LND dissection was not associated with an OS benefit (hazard ratio: 1.00; 95% confidence interval 0.97 to 1.04).

CONCLUSIONS

Among all RCC patients, LNDs are often performed for low stage disease, suggesting a potential overutilization of LND. No OS benefit was seen in any subgroup of patients undergoing LND. Further investigation is needed to determine which patient populations may benefit most from LND.

RETRACTED: Recommandations françaises du Comité de Cancérologie de l’AFU – Actualisation 2018–2020 : prise en charge du cancer du reinFrench ccAFU guidelines – Update 2018–2020: Management of kidney cancer

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). Cet article est retiré de la publication à la demande des auteurs car ils ont apporté des modifications significatives sur des points scientifiques après la publication de la première version des recommandations. Le nouvel article est disponible à cette adresse: DOI:10.1016/j.purol.2019.01.004. C’est cette nouvelle version qui doit être utilisée pour citer l’article. This article has been retracted at the request of the authors, as it is not based on the definitive version of the text because some scientific data has been corrected since the first issue was published. The replacement has been published at the DOI:10.1016/j.purol.2019.01.004. That newer version of the text should be used when citing the article.

Assessing lymph node status in patients with kidney cancer

Accurate detection of lymph node involvement on pre-operative imaging in patients diagnosed with renal cell carcinoma (RCC) is critical for determination of disease stage, one of the most significant prognostic factors in RCC. The presence of lymph node involvement in RCC doubles a patient’s risk of distant metastasis and significantly reduces their 5-year survival. Currently, lymph node involvement in patients with RCC is evaluated with numerous modalities, with rapid advancements occurring across these modalities. The purpose of this study was to evaluate the advantages and disadvantages of each modality and utilize sensitivities and specificities to determine the highest performing modalities for accurate lymph node involvement in renal cancer. A comprehensive computer-based literature search of full-length original research English language studies of human subjects with biopsy-proven RCC was performed to evaluate publications on the diagnostic performance of color Doppler sonography (CDS), magnetic resonance imaging (MRI), lymphotrophic nanoparticle enhanced MRI (LNMRI), multidetector-row computed tomography (MDCT), F-fluoro-2-deoxyglucose positron emission tomography (FDG-PET), and PET/CT for evaluation of lymph node status in kidney cancers in articles that were published prior to May 2018. Limited studies were available for evaluating CDS performance for determination of lymph node involvement in renal cancer. While CT is the most common modality for nodal staging, due to its availability and relatively low expense, it did not demonstrate the highest performance of the modalities examined for determination of lymph node status in patients with RCC. Of the modalities examined, MRI demonstrated the highest sensitivity (92–95.7%) for detection of lymph node involvement in RCC. Studies of lymph node involvement in RCC using both MRI and CT indicated that using the current diameter criteria (greater than 1 cm) for determination of positive lymph nodes should be re-evaluated as micro-metastases are frequently overlooked. Studies evaluating lymph node involvement with FDG-PET had the highest specificity (100%), indicating FDG-PET is the preferred modality for confirming lymph node involvement and extent of involvement. However, due to the low sensitivity of FDG-PET, clinicians should be skeptical of negative reports of lymph node involvement in RCC patients. Further studies examining determination of lymph node involvement in renal cancer across modalities are greatly needed, current literature suggests utilizing a combination of MRI and FDG-PET may offer the highest accuracy.

Predictive and prognostic effect of inflammatory lymphadenopathies in renal cell carcinoma

PURPOSE

A significant proportion of patients affected by renal cell carcinoma (RCC) shows a suspicious lymph node involvement (LNI) at preoperative imaging. We sought to evaluate the effect of lymphadenopathies (cN1) on survival in surgical RCC patients with no evidence of LNI at final pathology (pN0).

METHODS

719 patients underwent either radical or partial nephrectomy and lymph node dissection at a single tertiary care referral centre between 1987 and 2015. All patients had pathologically no LNI (pN0). Outcomes of the study were cancer-specific mortality (CSM) and other-cause mortality. Multivariable competing-risks regression models assessed the impact of inflammatory lymphadenopathies (cN1pN0) on mortality rates, after adjustment for clinical and pathological confounders.

RESULTS

114 (16%) and 605 (84%) patients (16%) were cN1pN0 and cN0pN0, respectively. cN1pN0 patients were more frequently diagnosed with larger tumours (8.4 vs. 6.5 cm), higher pathological tumour stage (pT3-4 in 71 vs. 36%), higher Fuhrman grade (G3-G4 in 64 vs. 31%), more frequently with necrosis (75 vs. 44%), and distant metastases (33 vs. 10%) (all p < 0.0001). At univariable analysis, inflammatory lymphadenopathies resulted associated with worse CSM (HR 2.45; p < 0.0001). However, at multivariable analysis, inflammatory lymphadenopathies were not an independent predictor of CSM (HR 0.81; p = 0.4). The presence of metastases at diagnosis was the most important factor affecting CSM (HR 6.54; p < 0.0001). This study is limited by its retrospective nature.

CONCLUSIONS

In RCC patients, inflammatory lymphadenopathies (cN1pN0) are associated with unfavourable clinical and pathological characteristics. However, the presence of inflammatory lymphadenopathies does not affect RCC-specific mortality.

The role of lymph node dissection in the management of renal cell carcinoma: a systematic review and meta-analysis

Our objective was to evaluate the role of retroperitoneal lymph node dissection (LND) in non-metastatic (M0) and metastatic (M1) renal cell carcinoma (RCC). We searched Medline, EMBASE, Web of Science and Scopus from database inception to 29 August 2017 for studies of patients who underwent partial or radical nephrectomy for M0 or M1 RCC. Two investigators independently selected studies for inclusion. Risk of bias was assessed using the Newcastle-Ottawa scale, Cochrane Collaboration tool and National Heart, Lung and Blood Institute Quality Assessment Tool. Random effects meta-analysis was performed for all-cause-mortality. The GRADE approach was used to characterize quality of evidence. A total of 51 unique studies were included in the qualitative systematic review. Risk of bias was low in 41/51 (80%) studies. LND was not associated with all-cause mortality in either M0 (hazard ratio [HR] 1.02, 95% confidence interval [CI] 0.92-1.12; I² = 0%; four studies), M1 (HR 1.04, 95% CI 0.83-1.29; I² = 0%; two studies), or pooled M0 and M1 settings (HR 1.00, 95% CI 0.92-1.09; I² = 0%; seven studies), with no statistically significant differences according to M stage subgroups (P = 0.50). In the three studies that examined M0 subgroups with a high risk of nodal metastasis, LND was not associated with improved oncological outcomes. Studies on the association of extent of LND with survival reported inconsistent results. Meanwhile, a small proportion of patients with pN1M0 disease demonstrate durable long-term oncological control after surgery, with 10-year cancer-specific survival of 21-31%. Nodal involvement is independently associated with adverse prognosis in both M0 and M1 settings. GRADE quality of evidence was moderate or low for the outcomes examined. Although LND yields independent prognostic information, the existing literature does not support a therapeutic benefit to LND in either M0 or M1 RCC. High-risk M0 patient groups warrant further study, as a subset of patients with isolated nodal metastases experience long-term survival after surgical resection.

Lymph node dissection should not be dismissed in case of localized renal cell carcinoma in the presence of larger diseases

OBJECTIVE

To assess whether even in the group of localized renal cell carcinoma (RCC), some patients might harbor a disease with a predilection for lymph node invasion (LNI) and/or lymph node (LN) progression and might deserve lymph node dissection (LND) at the time of surgery.

MATERIALS AND METHODS

Between 1990 and 2014, 2,010 patients with clinically defined T1-T2N0M0 RCC were treated with nephrectomy and standardized LND at a single tertiary care referral center. The endpoint consists of the presence of LNI and/or nodal progression, defined as the onset of a new clinically detected lymphadenopathy (>10mm) in the retroperitoneal lymphatic area with associated systemic progression or histological confirmation or both. We tested the association between clinical characteristics and the endpoint of interest. Predictors consisted of age at surgery, clinical tumor size, preoperative hemoglobin, and platelets levels. Multivariable logistic regression model and smoothed Lowess method were used.

RESULTS

LNI was recorded in 14 cases (2.2%). The median follow-up after surgery was 68 months. During the study period, 23 patients (1.1%) experienced LN progression; 91% of those patients experienced LN progression within 3 years after surgery. Combining the 2 endpoints, 36 patients (1.8%) had LNI and/or LN progression. Clinical tumor size was the only independent predictors of LNI and/or LN progression (OR = 1.25). A significant increase of the risk of LNI and/or LN progression was observed in RCC larger than 7cm (cT2a or higher).

CONCLUSIONS

LNI and/or LN progression is a rare entity in patients with localized RCC. Nonetheless, patients with larger tumors might still benefit from LND because of a non-negligible risk of LNI and/or LN progression.

Retroperitoneal Lymphadenectomy for High Risk, Nonmetastatic Renal Cell Carcinoma: An Analysis of the ASSURE (ECOG-ACRIN 2805) Adjuvant Trial

PURPOSE

Lymphadenectomy is a well established practice for many urological malignancies but its role in renal cell carcinoma is less clear. Our primary objective was to determine whether lymphadenectomy impacted survival in patients with fully resected, high risk renal cell carcinoma.

MATERIALS AND METHODS

Patients with fully resected, high risk, nonmetastatic renal cell carcinoma were randomized to adjuvant sorafenib, sunitinib or placebo in the ASSURE (Adjuvant Sorafenib and Sunitinib for Unfavorable Renal Carcinoma) trial. Lymphadenectomy was performed for cN+ disease or at surgeon discretion. Patients treated with lymphadenectomy were compared to patients in the trial who did not undergo lymphadenectomy. The primary outcome was overall survival associated with lymphadenectomy. Secondary outcomes were disease free survival, factors associated with performing lymphadenectomy and surgical complications.

RESULTS

Of the 1,943 patients in ASSURE 701 (36.1%) underwent lymphadenectomy, including all resectable patients with cN+ and 30.1% of those with cN0 disease. A median of 3 lymph nodes (IQR 1-8) were removed and the rate of pN+ disease in the lymphadenectomy group was 23.4%. There was no overall survival benefit for lymphadenectomy relative to no lymphadenectomy (HR 1.14, 95% CI 0.93-1.39, p = 0.20). In patients with pN+ disease who underwent lymphadenectomy no improvement in overall or disease-free survival was observed for adjuvant therapy relative to placebo. Lymphadenectomy did not confer an increased risk of surgical complications (14.2% vs 13.4%, p = 0.63).

CONCLUSIONS

The benefit of lymphadenectomy in patients undergoing surgery for high risk renal cell carcinoma remains uncertain. Future strategies to answer this question should include a prospective trial in which patients with high risk renal cell carcinoma are randomized to specific lymphadenectomy templates.

Surgical Management of Advanced and Metastatic Renal Cell Carcinoma: A Multidisciplinary Approach

The past decade has seen a rapid proliferation in the number and types of systemic therapies available for renal cell carcinoma. However, surgery remains an integral component of the therapeutic armamentarium for advanced and metastatic kidney cancer. Cytoreductive surgery followed by adjuvant cytokine-based immunotherapy (predominantly high-dose interleukin 2) has largely given way to systemic-targeted therapies. Metastasectomy also has a role in carefully selected patients. Additionally, neoadjuvant systemic therapy may increase the feasibility of resecting the primary tumor, which may be beneficial for patients with locally advanced or metastatic disease. Several prospective trials examining the role of adjuvant therapy are underway. Lastly, the first immune checkpoint inhibitor was approved for metastatic renal cell carcinoma (mRCC) in 2015, providing a new treatment mechanism and new opportunities for combining systemic therapy with surgery. This review discusses current and historical literature regarding the surgical management of patients with advanced and mRCC and explores approaches for optimizing patient selection.

Risk Assessment in Small Renal Masses: A Review Article

The incidence of localized renal cell carcinoma (RCC) has been steadily increasing, in large part because of the increased use of imaging. Optimizing the management of localized RCC has become one of the leading priorities and foremost challenges within the urologic-oncologic community. Adequate risk stratification of patients following the diagnosis of localized RCC has become meaningful in deciding whether to treat, how to treat, and how intensively to treat. This article characterizes the existing risk assessment models that can be useful as treatment decision aids for patients with localized RCC.

Lymph Node Dissection for Small Renal Masses

Because the majority of small renal masses (SRMs; <4 cm) demonstrate low metastatic potential and can be effectively treated with radical or partial nephrectomy, the role of lymph node dissection (LND) at the time of surgery is unclear. A randomized trial demonstrated no survival benefit of LND in clinically localized renal cell carcinoma. Thus, LND is not recommended routinely for SRMs. For patients with high-risk features or radiographic evidence of lymphadenopathy, however, LND may improve local staging and potentially provide a survival benefit. If performed, a LND template should be based on the known lymphatic drainage of the kidneys.

Radical Nephrectomy for Renal Cell Carcinoma: Its Contemporary Role Related to Histologic Type, Tumor Size, and Nodal Status: A Retrospective Study

OBJECTIVES

Staging for renal cell carcinoma (RCC) depends on tumor size and the status of the regional lymph nodes. Although lymph node involvement by tumor yields the most accurate staging and prognostic information in patients with carcinomas of various genitourinary organs, the role of lymph node sampling (LNS) in patients with RCC to definitively establish nodal metastases remains unsettled.

METHODS

In this retrospective study of 399 patients with RCC treated by total nephrectomy, 115 cases were subjected to lymph node dissection.

RESULTS

The corresponding primary tumors averaged  larger than 8 cm. Twenty-nine showed positive lymph nodes (25%). The present review confirms that primary tumor size is a key indicator of nodal involvement. Clear cell and papillary tumors larger than 4 cm involve lymph nodes more commonly than other types of RCC. Sarcomatoid differentiation occurred in all major cell types and existed in numbers too few to predict the likelihood of nodal metastases.

CONCLUSIONS

LNS in RCC for staging purposes may be warranted based on tumor size (>4 cm) as determined by imaging as well as histologic cell type, the latter suggesting a selective role for preoperative fine needle aspiration or core biopsy.

Radiographic size of retroperitoneal lymph nodes predicts pathological nodal involvement for patients with renal cell carcinoma: development of a risk prediction model

OBJECTIVES

To evaluate the ability of clinical and radiographic features to predict lymph node (pN1) disease among patients with renal cell carcinoma undergoing radical nephrectomy (RN), and to develop a preoperative risk prediction model.

PATIENTS AND METHODS

In all, 220 patients with preoperative computed tomography scans available for review underwent RN with lymph node dissection (LND) from 2000 to 2010. Radiographic features were assessed by one genitourinary radiologist blinded to pN status. Associations of features with pN1 disease were evaluated using logistic regression to develop predictive models. Model performance was assessed using area under the receiver operating characteristic curve (AUC) and decision curve analysis.

RESULTS

The median (interquartile range) lymph node yield was 10 (5-18). In all, 55 patients (25%) had pN1 disease at RN. On univariable analysis, the maximum lymph node (LN) short axis diameter [odds ratio (OR) 1.17; P < 0.001] predicted pN1 disease with an AUC of 0.84. Although several clinical and radiographic features were associated with pN1 disease, only two were retained in the multivariable model: maximum LN short axis diameter (OR 1.19; P <0.001) and radiographic perinephric/sinus fat invasion (OR 44.64; P = 0.01), with an AUC of 0.85. On decision curve analysis, the single variable and multivariable models showed similar net benefit.

CONCLUSION

Two radiographic features, maximum LN short axis diameter and perinephric/sinus fat invasion, outperformed traditional clinical variables in predicting pN1 disease. Maximum LN short axis diameter alone showed excellent predictive performance, and, if validated externally, would provide for a simple model to guide patient selection for LND.

Diagnostic and Prognostic Significance of Radiologic Node-positive Renal Cell Carcinoma in the Absence of Distant Metastases: A Retrospective Analysis of Patients Undergoing Nephrectomy and Lymph Node Dissection

The aim of this study was to evaluate the diagnostic and prognostic value of clinical-positive nodes at preoperative imaging (cN1) in patients with non-metastatic renal cell carcinoma (RCC) treated with lymph node dissection (LND). We retrospectively reviewed data for a cohort of 440 consecutive patients (cN0, 76.8%; cN1, 23.2%) with cTanyNanyM0 RCC who underwent nephrectomy and LND from 1994 to 2013. Metastasis-free survival (MFS) and cancer-specific survival (CSS) were estimated using the Kaplan-Meier method. Multivariate Cox regression analysis was performed to determine significant predictors of MFS and CSS. The mean number of lymph nodes (LNs) examined for all patients was 8.3, and pN1 disease was identified in 31 (7.0%). LN staging by preoperative imaging had a sensitivity of 65%, a specificity of 80%, and an accuracy of 77%. During a median follow-up of 69 months, 5-yr MFS and CSS were 83.6% and 91.3% in patients with cN0 and 49.2% and 70.1% in patients with cN1, demonstrating a trend toward worse prognosis with radiologic lymphadenopathy (all P < 0.001). Furthermore, differences in MFS and CSS between the cN0pN0 and cN1pN0 groups were significant (all P < 0.001). Clinical nodal involvement is an important determinant of adverse prognosis in patients with non-metastatic RCC who undergo LND.

Staging, surveillance, and evaluation of response to therapy in renal cell carcinoma: role of MDCT

Renal cell carcinoma is the most common malignant renal tumor in the adults. Significant advances have been made in the management of localized and advanced renal cell carcinoma. Surgery is the standard of care and accurate pre-operative staging based on imaging is critical in guiding appropriate patient management. Besides staging, imaging plays a key role in the post-operative surveillance and evaluation of response to systemic therapies. Both CT and MR are useful in the staging and follow up of renal cell carcinoma, but CT is more commonly used due to its lower costs and wider availability. In this article, we discuss and illustrate the role of multi-detector CT in pre-operative staging, post-operative surveillance, and evaluation of response to systemic therapy in renal cell carcinoma.

Preoperative predictors of pathological lymph node metastasis in patients with renal cell carcinoma undergoing retroperitoneal lymph node dissection

PURPOSE

Patients with locally advanced renal cell carcinoma represent a subset that may benefit from retroperitoneal lymph node dissection. We identified preoperative clinical predictors of positive lymph nodes in patients with renal cell carcinoma without distant metastasis who underwent retroperitoneal lymph node dissection.

MATERIALS AND METHODS

We retrospectively analyzed data on a consecutive cohort of 1,270 patients with cTany Nany M0 renal cell carcinoma who were treated at a single institution from 1993 to 2012. Multivariate analysis was performed to determine preoperative predictors of pathologically positive lymph nodes in patients who underwent retroperitoneal lymph node dissection. A nomogram was developed to predict the probability of lymph node metastasis. Overall, cancer specific and recurrence-free survival was estimated using the Kaplan-Meier Method.

RESULTS

We identified 1,270 patients with renal cell carcinoma without distant metastasis who had (564) or did not have (706) retroperitoneal lymph node dissection performed. Of the 564 patients 131 (23%) and 433 (77%) had pN1 and pN0 disease, and 60 (37%) and 29 (7.2%) had cN1pN0 and cN0pN1 disease, respectively. ECOG PS, cN stage, local symptoms and lactate dehydrogenase were associated with nodal metastasis on multivariable analysis. A nomogram was developed with a C-index of 0.89 that demonstrated excellent calibration. Differences in overall, cancer specific and recurrence-free survival among pNx, pN0 and pN1 cases were statistically significant (p <0.001).

CONCLUSIONS

Local symptoms, ECOG PS, cN stage and lactate dehydrogenase were independent predictors of lymph node metastasis in patients who underwent retroperitoneal lymph node dissection. Our predictive nomogram using these factors showed excellent discrimination and calibration.

Lymph node dissection during cytoreductive nephrectomy: a retrospective analysis

OBJECTIVE

To assess whether regional lymph node dissection could improve the prognosis of patients with metastatic renal cell carcinoma.

METHODS

We reviewed data on 258 patients who underwent cytoreductive nephrectomy at Memorial Sloan Kettering Cancer Center, New York, USA, some of whom received a concurrent lymph node dissection. The primary outcome measure was overall survival. A Cox proportional hazards regression model included, age, pathological stage, lymphadenopathy, tumor size, modified Memorial Sloan Kettering Cancer Center criteria, site of metastatic disease and lymph node dissection. We created a logistic regression model to evaluate risk factors for node-positive disease. Survival analyses were carried out for lymph node template (hilar vs other) and number of nodes removed (0-3, 4-7 or ≥8).

RESULTS

Of 258 patients, 177 (69%) underwent lymph node dissection, and positive nodes were found in 59 (33%). The 5-year overall survival was 21% for patients who underwent lymph node dissection and 31% for patients who did not. No significant difference in survival was found among patients receiving or not receiving lymph node dissection. The 5-year overall survival was 27% and 9% for negative and positive nodal status, respectively (P < 0.0005). For patients who underwent lymph node dissection, the presence of lymphadenopathy was a significant predictor of node-positive disease (odds ratio 25.0, 95% confidence interval 9.04-69.4, P < 0.0001).

CONCLUSIONS

Lymph node dissection carried out during cytoreductive nephrectomy is not associated with a survival benefit. Lymph node-positive disease represents a poor prognostic variable; therefore, lymph node dissection should be considered as a staging procedure for clinical trials.

When to perform lymph node dissection in patients with renal cell carcinoma: a novel approach to the preoperative assessment of risk of lymph node invasion at surgery and of lymph node progression during follow-up

OBJECTIVE

To identify preoperatively patients who might benefit from lymph node dissection (LND).

PATIENTS AND METHODS

We assessed lymph node invasion (LNI) at final pathology and lymph node (LN) progression during the follow-up for 1983 patients with RCC, treated with either partial or radical nephrectomy. LN progression was defined as the onset of a new clinically detected lymphadenopathy (>10 mm) in the retroperitoneal lymphatic area. Logistic regression analyses were used to assess the effect of each potential clinical predictor (age, body mass index, tumour side, symptoms, performance status, clinical tumour size, clinical tumour-node-metastasis stage, and albumin, calcium, creatinine, haemoglobin and platelet levels) on the outcome of interest. The most parsimonious multivariable predictive model was developed, and discrimination, calibration and net benefit were calculated.

RESULTS

The prevalence of LNI was 6.1% (120/1983 patients) and during the follow-up period, 82 patients (4.1%) experienced LN progression. On multivariable analyses, the most informative independent predictors were tumour stage (cT3-4 vs cT1-2, odds ratio [OR] 1.52, P = 0.05), clinical nodal status [cN1 vs cN0, OR 7.09, P < 0.001], metastases at diagnosis (OR 3.04, P < 0.001) and clinical tumour size (OR 1.14, P < 0.001). The accuracy of the multivariable model was found to be 86.9%, with excellent calibration and net benefit at decision-curve analyses.

CONCLUSIONS

By relying on a unique approach, combining the risk of harbouring LNI and/or LN progression during the follow-up period, we have provided the first clinical presurgery model predicting the need for LND.

The survival benefit of lymph node dissection at the time of removal of kidney, prostate and urothelial carcinomas: what is the evidence?

INTRODUCTION

Lymph node dissection (LND) has been advocated by oncologic surgeons to completely eradicate cancer. However, evidence for that strategy is solely based on poor quality data. Some randomized studies done outside the field of urology failed to show any benefit to LND. Our objective was to evaluate whether LND at the time of removal of prostate, kidney and urothelial carcinomas results in a survival benefit.

METHODS

For that purpose, we performed a systematic literature review.

RESULTS

For kidney cancer, LND might be able to cure some patients with N+ disease. In N0 patients, although a randomized trial has been completed, the value of LND remains uncertain. LND at the time of radical prostatectomy can be useful in some patients with lymph node invasion. However, studies on the impact of LND in pN0 patients are retrospective and conflictive. Extended LND has been recommended when performing a radical cystectomy based on improved outcomes observed in retrospective studies. However, these studies are limited by selection biases and results of ongoing randomized trials will specify the template and the advantages of LND when removing a bladder cancer. Recent data of large series of radical nephro-ureterectomies for upper tract urothelial carcinomas are conflicting. Some found a benefit of LND in N0 patients while others did not.

CONCLUSION

The studies that support LND at the time of surgery for prostate, kidney and urothelial carcinomas have low level of evidence. This should encourage urologists to design and perform well-designed randomized trials to assess the potential survival impact of a commonly done procedure.

Approach to the small renal mass: to treat or not to treat

Accurately conveying the benefits and risks of treatment interventions to patients diagnosed with small renal masses (SRMs) is essential to appropriately identify which patients will achieve better oncologic outcomes and confer a survival advantage from primary therapy. Treatment decisions to determine the ideal management with nephrectomy, thermal ablation, or active surveillance for patients diagnosed with an SRM remain highly complex. Existing prediction tools that incorporate various key clinical variables may facilitate an informed decision about the best management of SRM by more appropriately selecting treatment individualized to the characteristics of the SRM and the patient's clinical characteristics.

The role of lymph node dissection in renal cell carcinoma

The role of lymph node dissection (LND) in the staging and treatment of renal cell carcinoma has long been a topic of debate. The controversy has focused on whether LND is purely an adjunctive staging procedure or has a therapeutic role in the management of this disease. Potential benefits include enhanced staging, better selection for adjuvant therapies/clinical trials, a decrease in recurrence rates, and improved disease-specific and overall survival. This article reviews the available literature on LND in renal cell carcinoma and discusses the potential benefits of aggressive surgical resection in select high-risk patients.

Lymph node dissection in renal cell carcinoma

CONTEXT

Although lymphadenectomy (lymph node dissection [LND]) is currently accepted as the most accurate and reliable staging procedure for the detection of lymph node invasion (LNI), its therapeutic benefit in renal cell carcinoma (RCC) still remains controversial.

OBJECTIVE

Review the available literature concerning the role of LND in RCC staging and outcome.

EVIDENCE ACQUISITION

A Medline search was conducted to identify original articles, review articles, and editorials addressing the role of LND in RCC. Keywords included kidney neoplasms, renal cell cancer, renal cell carcinoma, kidney cancer, lymphadenectomy, lymph node excision, lymphatic metastases, nephrectomy, imaging, and complications. The articles with the highest level of evidence were identified with the consensus of all of the collaborative authors and were critically reviewed. This review is the result of an interactive peer-reviewing process by an expert panel of co-authors.

EVIDENCE SYNTHESIS

Renal lymphatic drainage is unpredictable. The newer available imaging techniques are still immature in detecting small lymph node metastases. Results from the European Organization for Research and Treatment of Cancer trial 30881 showed no benefit in performing LND during surgery for clinically node-negative RCC, but the results are limited to patients with the lowest risk of developing LNI. Numerous retrospective series support the hypothesis that LND may be beneficial in high-risk patients (clinical T3-T4, high Fuhrman grade, presence of sarcomatoid features, or coagulative tumor necrosis). If enlarged nodes are evident at imaging or palpable during surgery, LND seems justified at any stage. However, the extent of the LND remains a matter of controversy.

CONCLUSIONS

To date, the available evidence suggests that an extended LND may be beneficial when technically feasible in patients with locally advanced disease (T3-T4) and/or unfavorable clinical and pathologic characteristics (high Fuhrman grade, larger tumors, presence of sarcomatoid features, and/or coagulative tumor necrosis). Although node-positive patients often harbor distant metastases as well, the majority of retrospective nonrandomized trials seem to suggest a possible benefit of regional LND even for this group of patients. In patients with T1-T2, clinically negative lymph nodes and absence of unfavorable clinical and pathologic characteristics, regional LND offers limited staging information and no benefit in terms of decreasing disease recurrence or improving survival.

Can a durable disease-free survival be achieved with surgical resection in patients with pathological node positive renal cell carcinoma?

PURPOSE

Patients with isolated regional nodal metastases from renal cell carcinoma are a distinct cohort for which resection of involved lymph nodes may be therapeutic. We assessed the outcomes of patients treated at our institution with pathological node positive renal cell carcinoma without concomitant metastatic disease (T(any)N+M0).

MATERIALS AND METHODS

A total of 2,521 patients with nonmetastatic renal cell carcinoma (T(any)N(any)M0) of any histological subtype treated with nephrectomy were identified between 1995 and 2009. Pathological regional node positive disease in the absence of clinically detectable metastases (T(any)N(1-2)M0) was present in 68 patients (2.7%) and these patients formed our study cohort. Patients were assessed for timing and location of recurrence, disease specific survival and overall survival. Multivariate Cox regression analysis was performed to define factors predictive of recurrence and overall survival.

RESULTS

Of the 68 patients with T(any)N(1-2)M0 renal cell carcinoma 22.1% were free of disease at a median followup of 43.5 months. In those patients experiencing recurrence, disease was detected within the first 4 months after surgery in 51% and was most commonly detected at multiple organ sites. The Kaplan-Meier estimated 5-year overall survival and disease specific survival was 37% and 39%, respectively. Predictors of a favorable outcome included an Eastern Cooperative Oncology Group performance status of 0, single node involvement, absence of sarcomatoid features and papillary histology.

CONCLUSIONS

Nephrectomy with lymph node dissection can provide a durable disease-free survival in a proportion of patients with regionally advanced renal cell carcinoma and limited lymph node metastases.

Staging of renal cell carcinoma: Current concepts

The most important and widely utilized system for providing prognostic information following surgical management for renal cell carcinoma (RCC) is currently the tumor, nodes, and metastasis (TNM) staging system. An accurate and clinically useful staging system is an essential tool used to provide patients with counseling regarding prognosis, select treatment modalities, and determining eligibility for clinical trials. Data published over the last few years has led to significant controversies as to whether further revisions are needed and whether improvements can be made with the introduction of new, more accurate predictive prognostic factors. Staging systems have also evolved with an increase in the understanding of RCC tumor biology. Molecular tumor biomarkers are expected to revolutionize the staging of RCC by providing more effective prognostic ability over traditional clinical variables alone. This review will examine the components of the TNM staging system, current staging modalities including comprehensive integrated staging systems, and predictive nomograms, and introduce the concept of molecular staging for RCC.

The current role of lymph node dissection in the management of renal cell carcinoma

The role of lymph node dissection remains controversial in the surgical management of renal cell carcinoma. Incidental renal masses are being diagnosed at increasing rates due to the routine use of CT scans. Despite the increase in incidental diagnosis of renal masses, 20% to 30% of patients present with metastatic disease. Currently, surgeons do not routinely perform lymph node dissection unless there is gross evidence of lymphadenopathy, as patients without clinical evidence of lymphadenopathy rarely have positive nodes at the time of surgery. Patients with metastatic disease to the regional lymph nodes have a poor overall prognosis. However, some evidence supports a therapeutic benefit of lymphadenectomy in these patients. Further, the staging information gained from diagnosing lymph node involvement may allow for the use of new agents to treat metastatic disease and effect outcomes.